How do I remove or disable Voice Control on my iPhone 8 Plus

You can turn in Off based on Related Article -> Turn off Classic Voice Control on your iPhone, iPad, or iPod touch

⤵️

On an iPhone X or later, you can prevent Classic Voice Control or Siri from responding when you press and hold the Side button on your device. On an iPhone 8 or earlier, you can prevent Classic Voice Control or Siri from responding when you press and hold the Home button on your device. 

Follow these steps:

1. On an iPhone X or later, go to Settings > Accessibility, then tap Side Button. On an iPhone 8 or earlier, go to Settings > Accessibility, then tap Home Button.
2. Under Press and Hold to Speak, select one of these options:

• • Siri: Siri will respond when you press and hold the Home button.
  • Classic Voice Control: Classic Voice Control will respond when you press and hold the Home button. This will also turn off Siri.
  • Off: There will be no response when you press and hold the Home button.